Transient phosphorus depletion in the InP(001) surface layers induced by room temperature deposition of a thin Au film

Abstract

Au layers deposited on the InP(001)-p(2 × 4) surfaces at different deposition rates at room temperature have been studied in situ by means of LEED, AES and RBS-channeling techniques. At a deposition rate of 0.3Å/min, smaller by one order of magnitude than that for a Au layer epitaxially grown only by room-temperature deposition, it was found that the deposition of a Au film of monolayer thickness enhances the RBS intensity from In atoms within an interface region about 400Åthick by a factor of about 1.5, which represents complete depletion of P atoms over the corresponding depth. The depletion of P atoms was confirmed by direct detection by means of the QMA technique of the species with mass number 31 ejected just after Au deposition. It was also found that the anomalously enhanced RBS yield from In decays with a time constant of about 6 h and at the same time the AES yield from P increases somewhat. Furthermore, it was confirmed that no depletion of P atoms is induced by a blank test, namely only by heating at the same thermal flow as the Au layer was deposited. Such anomalous P depletion is discussed in relation to the mechanism for room-temperature epitaxial growth.